Internal-combustioit engine



1. FROELICH.

INTERNAL COMBUSTION ENGINE.

APPLICATION FILED DEC.3. 1915. '1 322 422, PatentedNoV. 18,1919.

I 6 SHEETS-SHEET I.

J. FROtLlCH. #NTERNAL COMBSTION ENGINE.

APPLICATioN FILED oma. 191s.

1 ,$22,422. Patented Nov. 18, 1919.

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Zizesses In Uerzr f5 E ghn, :24 T'OeZL'cz l (by .W @tig 1.FR0EL1GH. .Y lNTERNAL COMBUSTION ENGINE.

APPLICATION FILED DEC.3, 1915.

Patented Nov. 18, 1919.

6 SHEETS-SHEET 3.

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2. s, we 1 w/ J. FROELICH. INTERNAL comeusnoN ENGINE.

APPLICATION FILED DEC.3.1915.

Patented Nov. 18, 1919.

6 SHEETS-SHEEI 4.

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1. FnoEL'lcH.

INTERNAL COMBUSTION ENGINE.

APPLICATION FILED DEC.3, 1915- I Patented Nov. 18, 1919.

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\ 35h-71. -oelich J. FROEL'ICH.-

INTERNAL coMusUoN ENGINE.

APPLICATION FILED DEC.3. 1915. 1,322,422.

Patented Nov. 18, 1919.

J m W L. T m 6 U J/'e/z We@ Z i dh UN 1TB?? .STATES PAUL, MINNESOTA.` n

InVrEnNnL-oolyrrusrron ENGINE.

Applieaton filed December 3, 1915. Serial No.

To ZZ tti/0m t may concern.'

Be it known that LVJoHN Fnonmon, a citizen of the United States, 'residing at St. Paul, in the countyof Ramsey and `State of lilinnesota, have invented new and useful Improvements in Internal-Combustion Engines, of which the -following is a specification; Y v

My invention relates to improvements in internal combustion engines and ,more particularly to those of the two cycle type-,fin which the cylinders are' arranged in pairs and cooperate with each other in the introduction of fuel.

The general objects of the invention are to provide ai simple and eflicient engine of this class having means for thoroughly scavenging the cylinders after: each explosion andi for introducing charges of fuel of uniform quantity and composition into the cylinders and also to produce an operating cycle in whichthe scavenging and the'introduction of charges of fuel" shall be so related as to result in increased eliiciency.

To attain these objects I provide a pair of differential cylinders furnished with oppo-l sitelyy working differential pistons and employ a crank` case having aclosed com partnient for each cylinder. rllhe smaller compartment of each. differential ,cylinder constitutes the explosion chamber, and.,the larger compartment is the pump chan'iber for the gaseous fuel; Thev compartments in the crank caseserve 'air compression ch'ambers'for the scavenging air.A A transfer" or storage chamber, which receives 'gas from the pump chamber of Aone cylinderv and delivers it'into the explosion chamber ofthe other cylinder is alsoprovided. This transfer chamber is formed las apart yof the valve casing and the passage of scavenging air and freshgases is controlled entirelyfby a single rotary valvein said casing.;

This mechanism has been evolved to operate in the following cycle: Then the piston of one cylinderA has nearly completed its forward stroke the exhaust port inthe explosion chamber is uncovered thereby allowing said chamber to be relieved of deadgases. The inlet port is also uncoveredbyjsaid piston and air (which. has been drawn into the crank case of rsaid cylinder.A upon the previous return stroke and compressed in Saidchamber upon the forward'stroke of the piston) ispermitted to rush into said eX- plosionicha-unber and drive out the reinainingy Specification of Letters Patent.

Patented Nov. 18, 19179. Gasse.

burnt gases tlnough the exhaust port. At the beginning-of the return stroke of'said piston, fresh gas from the transfer chamber (which has been drawn frein a carburet'er intothe pump chamber of the other cylinder upon the last forward stroke of its piston and forced into said transfer 'chamber uponthe return stroke thereof) is admitted through the inta-ke port inthe explosion chamber in suiiicient volume to fill the saine and expel the scavenging air therefrom.

My invention also includes various novel features of construction, which are hereinafter particularly described and pointed out in the claims. l

` In thev drawings, Figure 1 is a central longitudinal sectional view of my improved engine; Figure 2 is a central transverse sectional view, taken through one of the engine cylinders; F ig. 3 is aside elevation of the engine; Figs. 4E, 5 and G are detail sectional vie'w's, showing the ports in the engine cylinders and are respectively taken through said cylinders on lthe lines 4 4, n, G-.G of F ig.`2; F ig.l7 is a longitudinal central sectional iew in detail of the rotary valve; Fig.` 8 i. side elevation thereof; Fig. 9is a plan view in detail of the valve casing; FigvlO is a. side elevation ofthe same; Figs'. ll to 1 8 are detail se'ctionalviews illustrating various parts of the valve and valve casing and also show the relation between the pistons andsaid valve; 'said sectional views are taken respectively on the lines indicated at lian, 12-12, iii-1e, M ii, i5 15, 16-16, 1?*17 and 1818 on each of Figs. 7,

S, 9, 10, 24E and 25.; Figs. 19 to Q2 are views' similarto Figs. 13 and 1-1- and show the pis` tons and valve i'n different relative positions; F ig. Qis a sectional view` indetail, showingavportion of the val-ve and transfer chamber and is taken onthe lines indicated by 23H23 in Figs. 7, S, 9, 10, 24e and 25; Fig. 24 is a diagrammatieal plan view of the innerl periphery of 'the bushings within the valve Casing showing 'the vformation and location of the ports therein and bearing reference lines nun'ibered lto vS, said lines corresponding in number ,and position with the radial lines in Fig. i235 Fig. 25 is a similar diagraminatyical plan vieu' of the outer periphery of they 7alve: Figs. 2G. 27 and 28 yare diagrammatical views, each showing both cylinders ofthe engine with the moving parts'in differentk relative positions, together with a representation ofv't-he position and movement of air, fresh gas and burnt gas-the air being indicated by circles, the gas by circles with a diametrical liner therein and the burnt gas by circles with a cross therein. Similar diagrammatic illustration of air and gas is also show in Figs. 19 and 22 respectively. Fig. 29 is a fragmei'rtary sectional view of the valve casing.

Referring to the accompanying drawings, l have used the reference letters A and .B to indicate the differential cylinders; These cylinders are identical and are mounted side by side upon a crank case C having therein a removable dividingv wall C formed of separable sections adapted to separate said crank case into compartments, one for each cylinder. A crank shaft 1 revoluble in the crank case C is formed with a crank 2 in each compartment, said cranks being ar ranged at 180 degrees with respect to each other. Di Eerential pistons A and B within the cylinders are connected by pitmen 3 with said cranks 2 and move in opposite directions.

The differential cylinders A and B comprise respectively explosion chambers a, il and pump chambers 5n and 5", said pump chambers being enlargements of the explosion chambers and located in axial alinement therewith. rlhe ex-plosion chambers da, 4b are respectively furnished with inlet ports Ga, 6h and with exhaust ports 7, 7" and are provided at their upper ends with the usual spark plugs (not shown) for igniting the gas in said cylinders. Said pump chambers 5a, 5b are respectively providedi'at their upper ends with a common inlet and outlet port S, Sb, which permits the passage of gas into and out of said chamber. The compartments or air compression chambers 9, 9b in the crank case C are each provided with a common inlet and outlet port numbered 10, 10b respectively. The differential pistons A and B comprises respectively working pisY tons a and and pump pistons a and 7.), the former fitting the explosion chambers at, 4b and the latter the pump chambers 5, 5". The working pistons aA and Z) compress gas within the explosion chambers 4;, 4J and receive impulses upon the ignition of the gas, while the pump pistons a and Z9 serve a double purpose, namely, to draw gas into the pump chambers 5, 5b and expel the same therefrom and also to draw air into the air compression chambers 9u, 9b and compress said air therein. y

A valve casing E containing a tubular rotary valve l) is secured horizontally upon the sides of the cylinders il and B, and said valve is rotated at the same rate as the crank shaft 1 through suitable gearing, such as a sprocket or toothed chain 11 connecting- Ythe valveD and crank shaft. with the valve casing E is the transfer or storage chamber E which communicates Cast integrally A with said valve. This valve casing is formed with conduits leading to the valve, which bring said valve into communication with the inlet 4ports of the explosion chambers 4ta, 4b, pump chambers 5, 5b and air compression chambers 9, 9b, and also With a carbureter 12 or other suitable source of gaseous fuel supply and the outer air. Said valve is designed (as will be hereinafter specifically pointed out) to 'permit the inflow of air from without to the air compression chambers 9a, 9b in the crank case and direct the same therefrom into the explosion chamber of the same cylinder, also to permit the inflow of fuel charges from the carbureter 12 to alternate pump chambers and direct the charges from each of said chambers, first, into the transfer chamber E', then, into the explosion chamber of the companion cylinder.

The valve casing E is a single casting having a longitudinal bore c for the valve D, a recess, comprising the transfer chamber E communicating with the bore c through an annular channel e and the following conduits and channels opening into said bore: conduits 12, 12 at the outer side of the casing connected through pipes 13, 13" with the carbureter 12; conduits 14, 14th also on the outer side of the casing opening through a pipe 15 into the outer air; depending conduits 16a, 16b leading respectively to the common inlet and outlet ports 8, 8b in the pump chambers 5a, 5"; depending conduits 17a, 17b leading respectively to the common inlet and outlet ports 10a, 10b of the air compression chambers 9a, 9b,`and channels 18a, 1Sb on the upper side of the casing openingrespectively iuto the inlet port-s 6u, G" of the explosion chambers ll, 4,

Machined bushings 19 and 19h, having ports therein rcgisteringwith the conduits and channels in the valve casing, are removably inserted in the ends of the bore c in similar angular relation to snugly receive the valve l) and further provide for arcurately fixing the points of ingress and egress to and from said valve. The inner ends of these bushings extend to the edges of the annular channel e in the bore c of the valve casing E, but do not obstruct said channel. Said bushings 19fL and 19h are provided with ports designated as follows: ports 20", 20, registering respectively with the gas inlet conduits 12, 12b in the valve casing E; ports 21a, 21b registering respectively with the gas conduits 16, 16b leading to the pump chambers; ports 22, 22b also registering respectively with said gas conduits 16, 16h; ports 233. 23" registering respectively with the air inlet conduits let, 14th; ports 24, 211 registering respectively with theV air conduits 17a, 17h, leading to the compression chambers 9a, 9b in the crank case C, and ports 25., 251 registering respectively wea-e2 the channels 18a, 18d?- which open into the inlet ports l6, Gliof ythe explosion'chanibersfll, 4b. The valve D fsdliolliv cylinder having journals d raty its ends landi, is revliiblyA mounted yin the bushii'igs '193,119'.l i The journals l turn'in roller bearings 26 mounted in bearing supports secured `upon theends of' tlie valve' casing E, and' one of said ournals Z lengtliened to pass tliifougliits sup-v port and furnish a line'ansfof connectionivith Said'valve is siipliilie'd withY the following designated; openings and channels arranged to register atce'rtain periods iii its rotation with 'the yportsl 'in the bushings"19%,Y 19?.; transverse channels 2Gb, registering respectively with the ports y 20?, 2121' and 20?, 21b; openings 27a, 27bfregistering respectivelyivith ports 22a, 22h; transverse cha-iinels 28, 28b registering respectively'vvitli the ings 29, -29h, registering respectively with said portsl V25a and 251?, and openings 30 in the middle of the valve communicating con# tinuously with the annular channel c in the valvecasing E, ivhicli opens into the transfer chamber E The openings and channels at one end of the valve, Whose reference numerals bear the letter' a' are identical in size and nuinberivith the openings and channels in the other end of thevalve, which bear the saine numerals With theletter b andthe corresponding openings and channels in said ends occupyv similar vlongitudinal positions, but at one end are diainetrieally opposed to those vat the other end.

The openings 29a, 29b inI the valve D,y

which permit fthe movement of gas from said transfer chamber E are so placed with respect to theintake openings 27a, 27D in said valve that the gais is compressed in said transfer chamber before each charge of fuel is delivered to an explosion chamber and when a passageway is cleared by the valve between said transferchsniber and one of the explosion` chambers the gasconiined in said transfer 'chamber expands andconipletel-y fills said explosion "chamber at 'atmospheric 'pressure .vTh/e channels 18a, 181 and inlet ports 6?, Gl?, of course, contain some of the expanded gases, but this inappreciable quantity is supplied from that thereto-l fore compressed Within the hollow portion of' the valve D.

T he operation of in y engine ivill now be described, taking as a convenient starting point in the operating cycle theexplosion of a charge in one of the cylinders. legiii-y ning With yan explosion in the cylinder (see Fig. 26), the'diiierential piston A" moves doivnivard on its Yforward stroke, theY piston t compressing the airin the compression chamber A9?, atpresent closed by the valve D k(lfig. 13)aiid drawing gas fromv` peratedbythe crank shaft 1.

the carburetei, through the transverse cha-niiel 26"A in the valve (F ig. y11) into the pump chamber 5a. The differential piston B in the companion cylinder Bis carried up! Ward, during saidY deivnivard .stroke of the diii'erentialpiston A", and its piston l; draws a supply of air, through the channel 28b inr the valve D'.(Fig.V 17), iiito the compression chamber 91 and compresses'. the gas for a sliert interval in the puinpchaniber5b, then forces said gas intoy the valve through the openin'gd27vb (Fig. 16) thence out through the openings 30,`in said valve into the transfer chamber E (Fig. '23). J ust beforey the piston@ in the cylinder A. reaches the end of its forward stroke (see Fig. 27), the inlet and exhaust ports 6@ vand 7a of the'expilosion chamber 4a' are uncovered by said piston. The uncovering or" the exhaust port 7 a releases tl'ie burnt gases and the opening of the inlet port G permits the inflow of scav` enging air from tlieair compression chainber9" through. the channel 28al in the valvev D (Fig. 19). rlgliis infloiviiig current of scavenging air strikes the baflie plate 3lav on the top of the piston a and is first deflected upward to reach and drive out all .of the burnt gases through theI exhaust port 7. The companion piston B at this tinie is completing the compression of' the gas in the explosion chamber 4l", also completing the expulsion of `the' gas from the pump chainiber'b and further, completing the Vintalre of air to the compression chamber 9b. f

At the beginning of the return stroke of the piston A in said cylinder A (Fig. 28) and before the inlet and exhaust ports 6a and 7av are covered by the piston a, a charge of gas 'from thev transferj chamber 'E' rushes through vsaid intake port into the explosion chamber 5L?. In reaching this explosion chamber said gas first passes from the trans fer chamber E` kthrough the openings 30 into the valve (Fig. 23),. then passes out of the valve through the opening 29a (Fig. 22), ivlience it is conducted through the channel 18L and said` inlet port 6a to said, explosion chamber la. The influx of' said gas displaces the scavenging air, as said scavenging air had displaced the burnt vgas, thus resulting in supplying said explosion chamber With a complete charge of fresh gas at atmospheric pressure, upon the initial return movement of the piston A. Continued upward Amovement ofl said piston A operates to compress the gasH Within the explosion chamber lla, force the gas from the pump chamber 5 k,through the valve D into the transfer chamber E via the port 27a (Fig. andports 30 (Fig. 23), and also draivs air through the transverse channel 28l1 in the valve (Fig. 18) into the compression chainber 9a. This completes one turn of the crank shaft and said operationV is repeated upon each revolution thereof.

iio

Having described my invention, what I claim as new and desire to protect by Letters Patent, is:

1. In an internal combustion engine, a plurality ofcoperating cylinders, a valve casing, including a transfer chamber formed with passageways therein, said casing-being secured upon the cylinders, a hollow rotary valve in the casing communicating constantly with said transfer chamber and provided with ports arranged to register with the passageways in said casing, said ports being adapted to receive gas from a suitable source of supply andL allow the escapeof said gas to said cylinders.

2. In an internal combustion engine, a pair of differential cylinders with oppositely working pistons therein, each cylinder comprising an explosion chamber and a pump chamber, the latter being adapted to supply gas for the explosion chamber of the companion cylinder, a carbureter, a valve casing including a transfer chamber and conduits leading from said carbureter to the pump chambers, and a single hollow rotary valve within said casing communicating continuously with said transfer chamber and provided with openings to permit and time the How of gas into and out of said valve through said conduits.

3. In an internal combustion engine, a pair of operating units each having an eX- plosion chamber, a pump chamber and an air compression chamber, a carbureter, a valve casing secured upon said cylinders and inclosing a transfer chamber, said casing being formed with conduits communieating with the chambers of each cylinder and also with 'said carbureter and the at mosphere, and a hollow rotary valve in said casing constantly opening into said transfer chamber and provided with channels to permit the passage of air from the aii` compression chamber of one cylinder to the eX- plosion chamber of the same cylinder, also having channels to permit the passage of gas from the carbureter to the pump chambers and formed with openings to permit the reception of gas from each pump chamber and to allow the escape of gas to the explosion chamber of the other cylinder.

4. In an internal combustion engine, a pair of differential cylinders, each comprising a pump chamber and an explosion chamber having a single inlet port and an eX- haust port; a crank case divided into com" partments, one for each cylinder; a differential piston, for each differential cylinder, Comprising a piston arranged to uncover the inlet and outlet ports at the end of its forward stroke, and a pump piston adapted to draw gas into the pump chamber and expel the same therefrom and also draw air into the crank case and compress said air therein, a transfer chamber, conduits connecting the pump chamber of each cylinder through said transfer chamber with the inlet port of the explosion chamber in the other cylinder; conduits connecting the crank case of each cylinder with the inlet port in the same cylinder and a single rotary valve designed to control the passage of air and gas in said conduits, so as to successively admit air and gas into each eX- plosion chamber during the period when the inletand exhaust valves are uncovered by their respective working pistons.

5. In an internal combustion engine, a pair of differential cylinders, each cylinder having a. pump chamber and an explosion chamber with an inlet and an exhaust port therein, a crank case, a removable wall. ar# ranged to divide the crank case int-o air compression chambers, one for each cylinder, pistons in Isaid cylinders working in oppo site directions, a carbureter, a valve casing including a transfer chamber and having a longitudinal bore therein, said bore communicating through passageways with the atmosphere and with said transfer chamber, carbureter, explosion chambers, pump cham bers and air compression chambers, a hollow valve revoluble in said bore, said valve having a plurality of ports and channels adapted to register with the conduits in the valve casing, said valve being` also adapted to admit air from without to the air compression chambers and direct the same from each cylinder into the corresponding explosion chamber and to admit the inliow of gas into the pump chamber of one cylinder, then direct said gas therefrom into the transfer chamber and finally admit gas from said transfer chamber into the explosion chamber of the other cylinder.

6. In an internal combustion engine, a pair of differential cylinders, each cylinder having a pump chamber and an explosion chamber with an inlet and an exhaust port therein, a crank case divided into air compression chambers, one for each cylinder, pistons in said cylinders working in opposite directions, a carbureter, a valve casing including a transfer chamber and having a longitudinal bore therein, said bore communicating through passageways with the atmosphere and with said transfer chamber, carbureter, explosion chambers, pump chambers and air compression chambers, removable bushings in said bore having ports therein communicating with the passageways in the valve casing, a hollow valve revoluble in said bore, and provided with journals at its ends, bearing support-s secured upon the ends of the valve casing and roller bearings in said supports for said journals, said supports being adapted to secure said bushings, in said valve casing, said valve having a plurality of openings and channels adapted to register with the conduits in the valve casing, said valve being also adapted to admit air from without to the air compression chambers and direct the same from each cylinder into the corresponding explosion chamber and to admit the inflow of gas into the pump chamber of one cylinder, then direct said gas therefrom into the transfer chamber and finally admit gas from said transfer chamber into the ex plosion chamber of the other cylinder.

In an internal combustion engine, a pair of diiferential cylinders, each comprising an explosion chamber having an inlet and exhaust port and a pump chamber formed with a common inlet and outlet port therein, a crank case divided into air compression chambers, one for each cylinder, each chamber being' supplied with a common inlet and outlet opening, oppositely working pistons in said cylinders, a carbureter, a valve casing having a longitudinal bore therein, said casing inclosing a transfer chamber and having a plurality of conduits opening` into said bore, viz.; conduits 12a, 12b leading to the carburetor, conduits 14?, 14th to the atmosphere, conduits 17a, 17" to the air compression chambers and conduits 16a, 1Gb to the pump chambers, said bore having an annular channel coinmunicating with the transfer chamber and channels 18", 181 each ofwhich opens into the inlet port of one explosion chamber, removable bushings in the ends of said valve casing, formed with ports registering with said conduits and diverging channels, a hollow tubular valve, revoluble in said bushings, having a channel at each end to permit the introduction of air through conduits 14", 14", thence through condu-its 17, 17h to the air compression chambers, whence the same may escape through the inlet ports into the eXplosion chambers, said valve also having a channel in each end to permit the introduction Aof gas from the carbureter through conduits 12, 12b, thence through the conduits 16, 161 to the pump chambers, said valve being further provided with an opening at each end to receive gas from said conduits 16, 16b as the same is expelled from the respective pump chambers, said valve being also formed with a plurality of central openings constantly communicating through said annular channel with the transfer chamber and with an opening in each end to permit the delivery of gas from the valve into each of the diverging channels, thence through the inlet ports into the explosion chambers, said openings and channels in said valve being so arranged that the charges of airand gas pass into each cylinder successively during the period when the exhaust port of that cylinder is open.

8` In an internal combustion engine, a plurality of coperating cylinders, a valve `casing having passageways therein and an integral transfer chamber communicating' therewith, a hollow rotary valve in said casing formed with openings providing constant communication between said chamber and the interior of the valve and also supplied with openings arranged to register with the passageways in said casing, whereby gas is permitted to enter the chamber through the valve and pass from said cham# ber through said valve directly into the cylinders.

9. In an internal combustion engine, a plurality of coperating cylinders, a valve casing having a longitudinal bore therein enlarged at one point to form an annular channel and also provided with conduits and with channels opening into said cylin ders, a chamber communicating with said annular channel, said casing having therein a hollow rotary valve provided with openings which communicate constantly 'with said chamber through said annular channel and further provided with openings and channels communicating with said channels leading to said cylinders, whereby both air and gas are conducted to said cylinders.

Whereof, I have hereunto subscribed my name to this specication.

JOHN FROELICH. 

